Stroke is a major public health problem in the United States. It is the fifth leading cause of death and a leading cause of serious disability in adults. There are an estimated 800,000 strokes in the United States each year, with more than 4.4 million stroke survivors. Twenty percent of stroke survivors require institutional care after 3 months and 15%-30% are permanently disabled. Recurrent events, which occur in 185,000 stroke survivors in the United States each year, are associated with higher mortality rates, greater levels of disability, and increased costs as compared with first strokes. Stroke in adults is strongly age dependent, and the rate of adverse outcomes and complications associated with stroke increases with advanced age. Because the United States population is aging, the population at risk for stroke and recurrent events will increase over the coming decades. Its high prevalence and associated deficits impose a large burden on patients, their families, and the healthcare system. Optimizing post-acute care and secondary prevention efforts for stroke survivors represents an important target to reduce the burden of recurrent stroke, particularly among the elderly. Racial- ethnic and regional disparities have been identified for stroke incidence, prevalence, and morality, but relatively little research has focused on potential disparities in the patterns of recurrent stroke events. The Patterns of Recurrent Stroke in the Elderly Study will use Medicare administrative data to achieve the following specific aims: 1) to determine rates of recurrent stroke in elderly Medicare beneficiaries hospitalized with ischemic stroke and assess disparities in recurrent rates by geographic and sociodemographic characteristics; and 2) to identify socioeconomic, healthcare access, lifestyle/comorbidity, and post-acute care factors that may contribute to variation in recurrent stroke events. Clinical practice, public policy, and reimbursement decisions are increasingly informed by data obtained from administrative datasets. The Patterns of Recurrent Stroke in the Elderly Study will be the largest contemporary investigation of recurrent stroke rates and patterns in the United States. Results from this project will identify geographic areas and subgroups that have distinctive health profiles that put them at high risk for recurrent stroke. Such information will inform care providers, insurers, public health agencies, and policy makers about communities that may derive the greatest benefit from targeted programs and community-based interventions.